I've always liked the idea of something like this LA to Vegas idea. This would work because between LA and Vegas are only maybe 3 stops (somewhere near San Bernardino, Victorville, and Barstow). But one thing I haven't seen mentioned is setting it up so you could load your car onto the train cheaper than you can drive. Without stopping much you could do the trip in about 2 hours and have your own car on either end. I think then it would work. It might even be faster than flying, when you count the checkin and checkout.
I think that this is where the article goes wrong. He mentions intermodal, but doesn't make it clear about what he is intermodal with. I think he is thinking airports and buses. Why not cars/interstates also?